Macro custom_print::define_dbglike

macro_rules! define_dbglike {
    (
        $( #[$meta:meta] )*
        $name:ident,
        $macro:path,
        expect,
        $format:literal,
        $($args:tt)*
    ) => { ... };
    (
        $( #[$meta:meta] )*
        $name:ident,
        $macro:path,
        try,
        $format:literal,
        $($args:tt)*
    ) => { ... };
}

Defines a dbg-like macro with a given name that uses specified write macro, error-handling policy, format string and writer.

The implementation of the generated dbg-like macro is based on std::dbg macro implementation, but the exact output printed by std::dbg should not be relied upon and is subject to future changes.

If the try policy is used, it propagates write error and returns values wrapper into Result.

The writer itself is specified by the rest arguments with the define_writer macros.

Examples

let mut string = String::new();
custom_print::define_dbglike!(cdbg, writeln, expect, ":?", fmt, |value: &str| string += value);
custom_print::define_dbglike!(try_dbg, writeln, try, ":?", fmt, |value: &str| string += value);

assert_eq!(cdbg!("first"), "first");
assert!(string.contains("\"first\""));
assert_eq!(try_dbg!("second"), Ok("second"));
assert!(string.contains("\"second\""));